Mortar dressing device



1967 M. SEBASTIAN! MORTAR DRESSING DEVICE Filed Jan. 18, 1965 INVE NTOR:

MART/IV SIB/45 T/A/V/ Attorneys United States Patent 3,302,233 MORTARDRESSING DEVICE Martin Sebastiani, Owingerstrasse 1, Uberlingen(Bodensee), Baden, Germany Filed Jan. 18, 1965, Ser. No. 426,020 Claimspriority, application Germany, Jan. 18, 1964, S 89,120; Jan. 13, 1965, 594,991 1 Claim. (Cl. l5235.4)

The present invention relates to a mortar-dressing device having ahollow section for applying, smoothing and floating of plasticmaterials, e.g. cementitious mortar.

The previous known devices of above type usually are constructed with arectangular hollow section, which ordinarily has an intermediateridgefor mechanical strength.

A disadvantage of mortar-dressing devices having flat parallel sides isthat they are very diflicult for masons to handle. The rectangularconstruction necessitates gripping holes which, in turn, disrupt thesmoothing surfaces. Another disadvantage of the above-mentionedrectangular-shaped hollow sections consists in non-existence of a sharpfloating edge suitable for pressing plastic materials, mortar, into thecorners of walls. The known dressing devices of rectangular-shapedhollow sections are of substantial weight, especially when theyincorporate for the reasons of mechanical reinforcement, an intermediateridge which forms a hollow section having an internal wall.

Another disadvantage of previous devices is that when they are used toform a level surface a guiding rod levelled by a plummet must beemployed. This not only necessitates the use of a second device butrequires additional time to orient the guiding rod with corners andedges.

Thus it is an object of the present invention to provide a betterhollow-shaped dressing device which, despite great mechanical strengthand lack of distortion, is very light in weight and easy to handlethereby greatly facilitating the smoothing of surfaces without breaks inthe continuity thereof.

It is another object of the invention to form the device in such amanner as to provide a sharp drawing edge and non-perforated smoothingsurfaces, the edges providing a means to press the plastic material intosharp corners.

It is another object of the invention to provide a device which is ableto perform the process of applying, smoothing and floating and levellingthe plastic surface.

The solution of the objects consists in providing the invention with ahollow section for applying, smoothing and floating of plastic materialand having smoothing and/ or applying surfaces. The working edge isformed by two acute angular smoothing surfaces running together and thewalls are formed of lightweight materials.

According to this main feature of the invention the acute angularsurfaces provide good gripping means for the masons, and eliminate, theneed to provide additional perforations in the smoothing surfaces. Thesharp drawing edge allows mortar to be pressed into corners or jointsand final floating of the mortar which was impossible with the previousrectangularly-shaped hollow sectioned tools.

One of the prefered embodiments of the invention is formed with atriangularly-shaped hollow section.

This shape provides an inexpensive and quick means of manufacturing thedevice, and has an extremely high resistance against longitudinal andvertical torsion. The tool is formed wtih oblique gripping and smoothingsurfaces.

A modified form of the invention has at least one convexly-shapedengaging and smoothing surface.

This convex shape also is characterized in having an extremely highresistance to longitudinal and vertical torsion. It provides bothslightly curved smoothing surfaces and a sharp drawing edge.

According to the invention the hollow section could be in the shape of arectangular trapezoid.

The base of the trapezoid and the acute angular leg thereof form thesmoothing surfaces. A trapezoidal hollow section also provides a highresistance to torsion and can be easily and inexpensively manufactured.

According to the invention, the drawing edge is provided with a shortradius of curvature to achieve a smooth flow of material at thesmoothing edge.

By providing such a curvature at the edge, injury to laborers will beprevented.

It is one of the expedients of the present invention to shape the hollowsection of aluminum or the like.

The use of aluminum provides a special saving of weight. It is of greatimportance for dressing rods of 2 meters in length or over. Moreover,the means of manufacturing aluminum tools are simple, e.g., injectionand/or pressure molding.

Another form of the invention consists in making the hollow section ofsynthetic material, the acute angular portion being reinforced with ametal ridge.

As the walls are of even thickness, the acute angular portion willalways show a certain accumulation of material, which lends the requiredstiffness to the drawing edge. If it is desirable to increase thestiffness thus preventing warping, i.e., distortion of longer dressingrods, this can be accomplished by inserting of metallic portions intothe interior of the hollow section. It is especially easy to do so, whenthe smoothing device is manufactured by extrusion molding. In that casea metallic pre-shaped rod will be extruded with synthetic material. Itis best to choose from the plurality of the possible synthetic materialsone which is abrasionresistant, stable and easy to handle, e.g.,polyurethane. If the synthetic material shows suflicient strength, thereis no need for reinforcement-portions and ribs of synthetic material canbe provided.

According to another feature of the invention, there is at least onewater level for levelling in the vertical and/ or the horizontalorientation of the tool which is positioned preferably at the middle ofthe longitudinal axis of the device.

The use of this dressing rod eliminates the need for a separate airlevel. Moreover, half of the time previously required for dressing ofthe rough cast will be saved. For more exact and versatile use, verticaland horizontal levels could be built in, i.e., the usual water or spiritfilled levels containing an air-bubble. Yet it is possible, to use onelevel for both directions by providing a concave covering glass for acircular-shaped level with a cross graduation. It is understood that itis necessary to use only one level if the device is to be used only inone direction.

For a better understanding of the invention, the following explanationin connection with the enclosed drawings is provided which, according tothe invention, illustrates the preferred types of the device. You willfind further features of the invention included in the description andthe drawings.

FIGURE 1 shows a perspective fragmentary view of the device according tothe invention, having a triangular hollow section.

FIGURE 2 shows a modified version of the hollow section of FIGURE 1.

FIGURE 3 shows another modification of the device of FIGURE 1.

FIGURE 4 shows a device according to the invention with a trapezoidalhollow section.

FIGURE shows a device according to the invention with two levels.

The dressing device according to FIGURE l consists of thin-walledaluminum and three walls forming a hollow section; the engaging legs 1,2 thereof forming smoothing surfaces 3, having convex shape. Theengaging smoothing surfaces 3 form an acute drawing edge 4, preferablyhaving a short radius of curvature. As can be seen, a device havingrelatively thin aluminum Walls will provide substantial resistanceagainst torsion. By having slightly convex-shaped smoothing surfaces 3,a safe gripping area is provided laborers, and no additional holds orperforations which could impair the function of the device are necessaryin the smoothing surfaces 3.

FIGURE 2 shows a modified version of the device, according to FIGURE 1,wherein only one smoothing surface 3 is of convex shape, while thesmoothing surface 5 and the leg thereof are flat planar surfaces.

The device of FIGURE 3 has legs 1, 2 which are straight, while thedrawing edge 4 is formed by the acute angular smoothing surfaces 5.

FIGURE 4 shows another modified version of the device according to theinvention, having a thin-Walled aluminum hollow section shaped as arectangular trapezoid. The base 6 together wth the acute angular leg 7form smoothing surfaces 5, 8, the intersecting line of which forms thedrawing edge 4. Accordingly the trapezoidal shape forms three smoothingsurfaces 5, 8, 9. Despite its light Weight it is very torque-resistantand has proper gripping means for the laborers.

The hollow section according to FIGURE 5 is also in the shape of arectangular trapezoid. The base 6 and leg 7 form two smothing surfaces5, 8 which meet at the edge 4. Opposite the base 6 lies a thirdsmoothing surface 9. In the surface 9 are two circular perforations 10,to provide for the levels 11. According to the illustrated example, theupper of these levels 11 lies parallel to the longitudinal edges, thusparallel to the drawing edge 4, while the lower level 11 lies parallelto the transverse edge of base 6. Thus one dressing rod could be usedfor horizontal as well as vertical dressing.

It is also to be seen from the illustrations that there is anaccummulation of material behind edge 4 which adds to the torqueresistance of the device. It is further understood, that by imbedding anadditional metal ridge at this location, further stiffness will beprovided.

It is of advantage to position the levels in the middle portion ofdressing rods of less than 2 meters in length. For dressing deviceslonger than 2 meters it is best to position the levels at about to cm.off ground, i.e., at eye level.

While the preferred type of the invention combines an aluminum or lightweight metal, it is possible to utilize extrusion type hollow sections,with or Without metal reinforcement ridges.

The features of this embodiment of the invention include a light weighthollow section having acute angular smoothing surfaces built in levels.

I claim:

A dressing device of the character described comprising, an elongatedhollow open-ended member having a pair of longitudinally extending wallsand a connecting longitudinally extending back member supporting inspaced relation each of said walls along one longitudinal edge thereof,said walls meeting in an acute angle in a common longitudinallyextending intersection portion to provide a longitudinally extendingdressing edge, one of said walls being formed to provide a convexsmoothing surface be tween said edge and back member, said walls beingof substantially uniform cross-section over their length and beingunsupported between said back member and intersecting portion to providesubstantially uniform lateral flexibility of said walls between saidback member and dressing edge, and said walls and back memberterminating on planes substantially perpendicular to the longitudinalaxis of said elongated member to define opposed open ends in said hollowmember.

References Cited by the Examiner UNITED STATES PATENTS 474,152 5/1892Taylor 33-206 999,573 8/1911 Lidholm 33206 1,768,411 6/1930 Lord l5235.42,450,385 9/1948 Schurnock l5235.4 2,608,852 8/1952 Whalen 15-23543,018,499 1/1962 Levy 15235.4 3,140,500 7/1964 Pilla l5235.4

CHARLES A. WILLMUTH, Primary Examiner.

S. E. BECK, Assistant Examiner.

